Product Description Features include: Precision diamond ground carbide tipped tip for exact pilot drilling. High temperature brazed carbide tip, straight shank. drill bit surface: silver. It is a tool for punching holes in glass, mirrors, tiles and ceramics material. Carbide cutting edge, straight shank Spear point, galvanized surface Best results under lower speed and good cooling with water, vinegar, etc. Ideal for drilling window panes, glass, mirror glass
